In 1849, Karl Marx arrived in London as a German-Jewish political refugee. Across the Continent, the revolutions of 1848 were being bloodily suppressed. In Britain, however, Marx (bankrolled by his capitalist friend Engels) flourished under the "bourgeois" institutions they plotted to overthrow: the rule of law, parliamentary democracy and the market economy. Yet it didn't occur to the author of Das Kapital to revise his ideas. He turned a blind eye to the fact of prosperity and liberty in Victorian Britain, insisting that "the proletarians have nothing to lose but their chains". The British proletariat actually had a good deal to lose: their only chains were their watch-chains. Although Marx stayed in Britain for 34 years until his death, his impact on its politics was insignificant.

A century after Marx's arrival, his most devoted disciples were still convinced that the master was correct: once capitalism collapsed under the weight of its contradictions, the British would embrace a socialist revolution. One of the most prominent of these fundamentalists was Ralph Miliband. Today, he is remembered less for his intellectual than for his physical progeny: for the past three months, his sons David and Ed have dominated the struggle for the soul of the Labour Party. At the time of writing, it is not clear which of the brothers will prevail. But their father always rejected Tony Crosland's social-democratic vision, to which they, like Tony Blair, subscribe. For him, there could be no compromise with capitalism. Would he have been proud if one of his sons were to become PM? Only as a means to the abolition of Britain as we have known it.

Amazingly, the brothers' political ascent has gained their father new admirers. John Gray sees Ralph as more prescient than his sons, in exposing the "bankruptcy" of the idea that capitalism would supply endless economic growth. "Ralph Miliband's pessimistic assessment of the future of social democracy could well be vindicated," Gray wrote in the Guardian. Thanks to the liberal habit of denouncing capitalism, now fashionable again, Miliband père has suddenly become grotesquely overrated.

Like Marx, Ralph was a refugee; unlike Marx, he was fleeing persecution not for being a socialist but simply for being Jewish. Aged 16, he arrived on the eve of the Battle of Britain. Unlike most of his family and friends on the Continent, he survived the war and the Holocaust, but it never occurred to him to admire the political system of the country in which he had found sanctuary. The first place he visited in London was Highgate Cemetery, where he stood before Marx's grave and swore a clenched-fist oath of allegiance. For the next half a century, he never wavered in his determination to bite the hand that had fed him.